WO2003000619A1

WO2003000619A1 - Ceramic component and production method therefor

Info

Publication number: WO2003000619A1
Application number: PCT/JP2002/006077
Authority: WO
Inventors: Hidenori Katsumura; Ryuichi Saito; Tsukasa Wakabayashi; Hiroshi Kagata
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 2001-06-25
Filing date: 2002-06-18
Publication date: 2003-01-03
Also published as: US20040041309A1; KR20030059109A; JP3807257B2; EP1403228B1; JP2003002751A; CN1207249C; CN1463261A; DE60217866T2; EP1403228A1; EP1403228A4; DE60217866D1

Abstract

A high-reliability, high-dimension-accuracy ceramic component having electric characteristics thereof not significantly deteriorated and defects such as cracks restricted in the vicinity of an internal electrode in a substrate after firing when subjected to a high-dimension-accuracy firing method in which a glass ceramic laminate is fired while being held between heat shrinkage restricting sheets. A method of producing a ceramic component comprising the conductor printing step of printing on a glass ceramic green sheet a conductor paste having a sintering speed equivalent to that of the glass ceramic green sheet, the laminating step of laminating a plurality of the glass ceramic green sheets to form a laminate, a composite laminating step of further laminating on the one or both surfaces of the laminate heat shrinkage restricting green sheets mainly containing inorganic matters, a binder removing step of removing by burning organic matters from the composite laminate, the firing step of sintering the organic matter-removed composite laminate with sintering behaviors of the glass ceramic green sheets and the conductor paste matched, and the step of removing inorganic matters in the heat shrinkage green sheets.

Description

Ceramic parts and manufacturing method

The present invention relates to a ceramic component typified by a ceramic multilayer substrate on which, for example, a semiconductor IC, a chip component, and the like are mounted and interconnected, and a method of manufacturing the same. Background art

In recent years, semiconductor ICs, chip components, and the like have been reduced in size and weight, and small and light-weight wiring boards for mounting them have been desired. Ceramic multilayer substrates are gaining importance in today's electronics industry because of the required high-density wiring and the ability to be made thinner.

A general method for manufacturing a ceramic multilayer substrate is as follows.

(1) Mixing and mixing of ceramic materials.

(2) Forming process of ceramic dust sheet.

(3) Conductive paste preparation process.

(4) A firing step of the composite laminate including the green sheet layer and the conductor layer.

In the above firing step, the ceramic multilayer substrate undergoes shrinkage due to sintering. Shrinkage due to sintering differs depending on the substrate material used, green sheet composition, powder mouth, etc. For this reason, there are some problems in the production of the multilayer substrate. One important issue is the shrinkage error. In the manufacturing process of the ceramic multilayer substrate, the innermost wiring is fired and then the uppermost wiring is formed. For this reason, when the contraction error of the substrate material is large, connection with the inner layer electrode cannot be performed due to a dimensional error with the uppermost wiring pattern. In order to avoid this, a land with an unnecessarily large area must be formed on the uppermost electrode to allow for the shrinkage error in advance, which is suitable for use in circuits that require high-density wiring. Absent. As a countermeasure, there is a method of preparing several screen plates for the top layer wiring according to the shrinkage error and using it according to the shrinkage ratio of the board. It must be prepared, which is uneconomical. On the other hand, if the simultaneous firing method in which the formation of the top wiring is performed simultaneously with the firing of the inner wiring is used, a large land is not required, but another problem remains. In other words, since the shrinkage error of the substrate itself exists as it is, in the cream solder printing process at the time of the final component mounting, printing may not be performed on a necessary portion due to the shrinkage error.

Further, Patent Publication No. 2785554 describes that a desired number of green sheets each formed of a low-temperature sintered glass-ceramic mixed powder and having an electrode pattern formed thereon are laminated on both sides or one side of the laminated body. The glass-ceramic mixed powder is laminated so as to be sandwiched between heat-shrinkage suppressing green sheets (hereinafter referred to as heat-shrinkage suppression sheets) made of an inorganic composition that does not sinter at the firing temperature of the glass-ceramic mixed powder. A method of removing the constrain layer is disclosed. As an effect, a large amount of firing of the substrate material occurs in the thickness direction, and a substrate in which shrinkage in the planar direction is suppressed can be manufactured, and the above problem can be solved. Although the method described in the above publication can provide a substrate that is unlikely to shrink in the planar direction, it has a problem that remains. That is, since a large amount of substrate shrinkage occurs in the thickness direction, cracks and other defects occur around the internal electrodes of the fired substrate.

The cause of this problem is considered to be largely due to the difference in the sintering timing or heat shrinkage behavior between the conductor paste and the green sheet laminate during the firing process. Since there is a large difference in the sintering shrinkage behavior between the green sheet laminate and the conductive paste, excessive stress and strain are generated between the fired substrate and the electrode, and the above-described defects such as cracks are generated. Occurs.

In the case of a normal firing method, shrinkage occurs in the three-dimensional direction in the firing process, and the generated cracks are repaired during firing if the cracks are minute. Since the shrinkage does not occur, defects such as cracks that occur once are difficult to repair. If defects such as cracks occur in the substrate, there is a problem in that the reliability of the substrate is reduced. Disclosure of the invention

The present invention solves the above-mentioned problems of the conventional manufacturing method. The purpose of the present invention is to provide a high dimensional accuracy firing method in which a glass-ceramic laminate is sandwiched between heat shrinkage suppressing sheets and fired. An object of the present invention is to provide a ceramic component having high reliability and high dimensional accuracy, which suppresses generation of defects such as cracks around internal electrodes in a fired substrate without causing the substrate to fire.

In order to achieve this object, a method for manufacturing a ceramic component according to the present invention comprises: a conductor printing step of printing a conductor paste having a sintering rate equivalent to that of the glass ceramic green sheet on a glass ceramic green sheet; A laminating step of laminating glass ceramic green sheets to form a laminate, and further laminating a heat shrinkage suppressing green sheet mainly composed of an inorganic material on one or both sides of the laminate to form a composite laminate. A composite laminating step, a binder removing step of incinerating and removing organic matter from the composite laminated body, and sintering the composite laminated body after removing the organic matter while matching the sintering behavior of the glass ceramic green sheet and the conductive paste. A method for producing a ceramic component, comprising: a firing step; and a step of removing an inorganic substance in the heat-shrinkable green sheet. Reliable ceramic components with high dimensional accuracy can be obtained. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a cross-sectional view illustrating a firing method of the present invention in which a ceramic laminate is sandwiched between heat shrinkage suppressing sheets and fired.

FIG. 2 is a cross-sectional view illustrating a defect occurrence location near a conductor layer. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described.

First, a method for manufacturing a glass ceramic mixed material will be described. The glass-ceramic mixed material used this time was alumina A1203, magnesium oxide AM g A main component is a mixture of samarium Sm203 (hereinafter AMS mixture) and glass (Si02-B203-CaO-based glass powder, softening point 780 ° C). High purity A1233, MgO, Sm203 raw material powder is weighed at a molar ratio of 11: 1: 1, put into a pole mill, mixed for 20 hours, and dried. This mixed powder was calcined at 1300 ° C. for 2 hours, and the calcined powder was ground with a pole mill for 20 hours to obtain AMS powder. The AMS powder and the Si〇2-B203-CaO-based glass powder were weighed in a weight ratio of 50:50, mixed with a pole mill for 20 hours, and then dried to obtain a glass-ceramic mixed material (hereinafter, referred to as “a”). AMSG material) is obtained. Since this AMS G material is densely fired in the temperature range of 880 ° C to 950 ° C, it can be fired simultaneously with the silver electrode. The relative permittivity is 7.5 (1MHz).

Alumina powder (purity: 99.9%, average particle size: 1.0 ^ m) was used as a material of the heat shrinkage suppression green sheet 10 shown in FIG.

PVB resin as a binder and dibutyl phthalate as a plasticizer are added to the above-mentioned AMSG material and alumina powder, and a slurry is prepared using butyl acetate as a solvent. (AMS green sheet) 20 and heat shrinkage suppression (alumina) green sheet 10 were produced.

Next, a method for producing the conductor paste will be described.

Of silver powder 1 00% by weight, the additives are mixed in an arbitrary ratio, an organic vehicle (Tabineoru lysate E chill cellulose) 20 by weight ^_0/0 applied to the entire paste, three of these ceramics The mixture was kneaded with a roll to obtain a conductor paste. This conductor paste is printed on the AMSG green sheet 20 as a pattern for measuring electric resistance (conductor layer 30) using a screen printing machine, and then the required number of AMSG green sheets 20 are laminated as shown in FIG. Then, an alumina green sheet 10 is laminated on both sides. In this state, the laminate was formed by thermocompression bonding. The thermocompression bonding conditions were a temperature of 80 ° C and a pressure of 500 kg / cm2. The laminate is cut to a size of 10 x 1 Omm, placed on an alumina sheath, and placed in a box furnace. Heat-treat at 0 ° C for 10 hours. After incineration of the resin components by heat treatment, the temperature was raised to 900 ° C in air at a temperature rising rate of 300 ° CZh (however, in Embodiment 3 the temperature raising rate was changed). The firing was performed under the condition of maintaining the temperature at 900 ° C. for 30 minutes. The alumina of the heat shrinkage suppressing green sheet 10 remained on the surface of the fired laminate without firing, and this was completely removed by ultrasonic cleaning in butyl acetate.

(Embodiment 1)

In the first embodiment, the effect of adding molybdenum oxide to the conductor paste will be examined. Table 1 shows the amounts of molybdenum trioxide (average particle size 2.5 μπι) added to silver powder (average particle size 4.O ^ m) and the results of analysis and evaluation of the obtained ceramic multilayer substrates. See Table 1.

In the table, * indicates a comparative example for the present invention. In the evaluation items, the “mode of defects such as cracks” indicates that the substrate 11 was polished and the cross section of the substrate was observed with an optical microscope as shown in FIG. The defects 13 such as cracks generated in the above are classified into the modes A, B and C shown below.

(Defect 13 mode classification)

"Mode AJ---- No defects.

"Mo-KB J-one--if the maximum length of the defect is small, less than 5 / z m.

“M-CJ-— When the maximum length of the defect is 5 μππ or more. The sheet resistance is defined by applying a silver electrode paste to the side surface of the inner conductor layer and baking to form a terminal electrode. It is a value calculated from the DC resistance value measured using a meter and the measured electrode thickness value, in terms of an electrode area of 1 mm2 and an electrode thickness of 10 μm.

In the case of adding no molybdenum trioxide, Sample No. 1, the addition amount was small, and in Sample No. 2, a large defect occurred near the conductor layer (Mode C). In contrast, cracks and other defects were not observed in Sample Nos. 3 to 7 in which molybdenum trioxide was added in an amount of 0.1% by weight or more (Mode A). It is considered that the addition of molybdenum trioxide makes it possible to delay the sintering of the conductor layer and to approximate the sintering behavior of the glass ceramic laminate. If the amount is less than 0.1% by weight, the sintering of the conductor paste cannot be sufficiently delayed. On the other hand, when the amount of addition is too large as 6.0% by weight as in Sample No. 7, the sheet resistance value of the conductor layer exceeds 6πιΩ and increases rapidly. It generated effectively suppressed defects and to maintain a low resistance value, the amount of the trioxide molybdenum 0. 1% by weight to 5. 0 wt ^_0/0 is preferred.

(Embodiment 2)

In the second embodiment, the effect of the particle size of the silver powder constituting the conductive paste was examined. As shown in Table 2, silver powder having an average particle size of 2.2 to 0.2 μππ was used, and 1.0% by weight of molybdenum trioxide was added to 100% by weight of each conductor powder. Prepared and evaluated conductive paste

(Table 2)

No defects were observed in the vicinity of the conductor layer in Sample Nos. 4 and 8 to 10 in which the silver powder particle diameter was 3 μm to 8 μm, but in Sample No. 12 in which the silver powder particle diameter was 2.2. In sample No. 11 as large as 10.2 m, a small defect was generated at the tip of the internal electrode (mode B). If the particle size of the silver powder is too small, the surface of the silver powder is activated, so that the temperature at which silver powder starts shrinking and shrinking becomes faster. If the particle size of the silver powder is too large, the temperature at which silver powder shrinks starts. It is thought that the difference in shrinkage behavior between the conductor layer and the glass-ceramic laminate is too large to cause a defect near the electrode. The resistance value hardly changed with the particle size of the silver powder.

From the above results, the particle size of the silver powder constituting the conductor layer is 3 μπ! It is desirable to be in the range of ~ 8 / zm.

(Embodiment 3)

In the third embodiment, the effect of the heating rate in the firing process was examined. The paste used had a silver powder particle size of 4.0 m and an added amount of molybdenum trioxide of 1.0 weight ⁰ /. This is the paste of sample number 4 of the sample. Table 3

As shown in Table 3, in Sample Nos. 4 and 14 to 17 where the average heating rate was in the range of 200 ° C / hour to 5500 ° CZ time, no defects were observed near the conductor layer, but the average Sample No. 13 with a slow heating rate of 100 ° CZh had a slight defect (M KB). Defects were also observed in Sample No. 18, which had a very fast heating rate of 9000 ° C / h. If the rate of temperature rise is reduced, it is considered that defects occurred because the time difference between the shrinkage behavior of the conductor layer and the glass ceramic laminate during firing increased. If the rate of temperature rise is too fast, a sudden contraction force acts near the conductor layer, and it is assumed that defects have occurred.

From the above results, it is desirable that the average temperature rise rate in the firing treatment step is 200 ° C / h to 5500 ° CZh. Although the above embodiment has been described using molybdenum trioxide, similar effects can be obtained by using other molybdenum oxide. The mixing ratio of the other molybdenum oxide is preferably from 0.1% by weight to 5.0% by weight in terms of dimolybdenum trioxide. In the embodiment of the present invention, (A 1203—Mg O—Sm2〇3) + glass-based material is used as the glass ceramic material. Tanoid oxide LnxOy (Ln is at least one selected from La, Ce, Nd, Sm, Eu, Gd, and Tb, and X and y are stoichiometrically determined according to the valence of Ln. It has been confirmed that the same effect can be obtained because the sintering shrinkage behavior does not change even if the value is used.

Further, the production method of the present invention can be used for other glass ceramics other than the glass ceramic comprising the above (A1203-MgO-LnOx) and a glass-based material. Industrial applicability

By using the method for manufacturing a ceramic component of the present invention, a high dimensional accuracy firing method in which a glass ceramic laminate is sandwiched between heat shrinkage suppressing sheets and fired without significantly deteriorating electrical characteristics, It is possible to provide a highly reliable and high dimensional accuracy ceramic component which suppresses generation of defects such as cracks around the internal electrode.

Claims

The scope of the claims

1. A conductor printing step of printing a conductor paste having a sintering rate equivalent to that of the glass ceramic green sheet on the glass ceramic green sheet, and laminating a plurality of the glass ceramic green sheets to form a laminate. A composite laminating step of further laminating a heat-shrinkage-suppressing green sheet containing an inorganic substance as a main component on one or both surfaces of the laminate to form a composite laminate; and removing the organic matter from the composite laminate by incineration. A binder step, a firing step of sintering the composite laminate after removing the organic substance by matching the sintering behavior of the glass ceramic green sheet and the conductive paste, and a step of removing an inorganic substance in the heat-shrinkable green sheet. Manufacturing method for ceramic parts, including

2. The sintering step is a step of suppressing the sintering speed of the conductor paste by molybdenum oxide mixed in the conductor paste, and performing sintering in accordance with the sintering speed of the glass ceramic. 1. The method for producing a ceramic component according to 1.

3. The conductor paste used in the conductor printing step contains silver powder and molybdenum oxide, and the compounding ratio of the molybdenum oxide is 0.1 to 5% by weight (in terms of molybdenum trioxide) of the entire conductor powder. 1. The method for producing a ceramic component according to 1.

4. In the firing step, the silver powder used for the conductor paste has an average particle size of 3 μn! The method for producing a ceramic part according to claim 1, wherein the step of controlling the shrinkage starting temperature of the conductive paste is performed by selecting silver powder having a size of 88 μm and matching the shrinkage behavior of the glass ceramic. .

5. The method of claim 1, wherein the conductive paste used in the conductive printing step contains silver powder and molybdenum oxide, and the silver powder has an average particle size of 3 / Xm to 8 μm. .

6. The ceramic according to claim 1, wherein the firing step includes a temperature raising step and a high temperature holding step, and the temperature raising rate in the temperature raising step is set to 200 ° C to 550 ° C per hour. The method of manufacturing the part.

7. Glass with acid oxide anoremi, magnesium oxide and specific lanthanoid oxide 7. The method for producing a ceramic component according to claim 1, wherein the glass ceramic green sheet is used.

8. A laminated glass ceramic component having a conductor layer of a predetermined pattern, wherein the glass ceramic includes aluminum oxide, magnesium oxide and a specific lanthanide oxide and glass, and the conductor has silver as a main component. A ceramic electronic component containing 0.1 to 5% by weight of molybdenum oxide in the entire conductor powder.